FIG. 1 illustrates the parts and function of a toilet of the prior art. Toilet 10 includes tank 20 and bowl 12. Tank 20 further includes overflow tube 22, and flapper 24. The normal water level in the tank is also indicated (W2). Bowl 12 further includes flush holes 16 disposed in rim 14. Siphon 18 is disposed at the rear of bowl 12. Water from bowl 12 enters siphon 18 and establishes a water trap which prevents gas from the sewer line from entering bowl 12. The water level within the bowl is indicated (W1).
Water inlet 15 is disposed between tank 20 and bowl 12 and provides fluid communication there between. Specifically, when the toilet is flushed by depressing the flush handle (not shown), flapper 24 is raised and water from tank 20 enters water inlet 15. From water inlet 15, a volume of water travels through rim 14 and enters bowl 12 through flush holes 16. The bulk of the water enters bowl 12 through a large flush hole 16a near the rear rim 16.
The large volume of water entering bowl 12 from tank 20 enters quickly and fills siphon 18. Once siphon 18 is filled, suction pulls the water out of bowl 12 and down the sewer pipe (not shown). Once bowl 12 empties, air enters siphon 18 (which produces the distinctive gurgling sound) which stops the siphoning process. Flapper 24 then closes and tank 20 is refilled with water. The flow of water from tank 20 into bowl 12 is shown in FIG. 1 by solid arrows.